A telecommunication network power system usually includes an AC-DC stage converting the power from the AC utility line to a 48V DC distribution bus and a DC-DC stage converting the 48V DC distribution bus to a plurality of voltage levels for all types of telecommunication loads. The DC-DC stage may comprise isolated DC-DC converters. Isolated DC-DC converters can be implemented by using different power topologies, such as flyback converters, forward converters, half bridge converters, full bridge converters and the like. The outputs of the isolated DC-DC stage may function as intermediate power buses (e.g., 12V intermediate power bus) for the telecommunication network power system.
The intermediate power buses may have a relatively wide voltage range. For example, an intermediate power bus may be specified to be 12V. The intermediate power bus may have a range from 9V to 15V in consideration with input voltage fluctuations. A plurality of downstream non-isolated dc/dc converters may be coupled to the intermediate power bus. The downstream non-isolated dc/dc converters may generate a variety of voltage levels in accordance with the needs of the telecommunication network power system.
The non-isolated dc-dc converters can be implemented by using different power topologies, such as buck dc-dc converters, boost dc-dc converters, buck-boost dc-dc converters, linear regulators and/or the like.